Barbara Nell

1 Introduction Refraction is the process by which light is bent as it passes through the ocular media, primarily the cornea and the crystalline lens, to focus accurately on the retina. Although most dogs are close to emmetropic, breed-specific and individual variations exist, and even mild refractive errors may impact visual performance, particularly in working or performance dogs [1-6].

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1 Introduction Certain breeds of dogs, like the Bloodhound, St. Bernard, and Spaniel, exhibit distinctive diamond-shaped eye openings that can lead to persistent conjunctival exposure, including impaired tear distribution and lower ectropion. Additionally, these breeds often present with heavy facial skin folds and hanging ears.